Metabolic flux analysis of clostridium thermocellum

Low-cost biochemical and/or fuel production from lignocellulosic materials is a national research focus. Few microorganisms are able to produce enzymes for degrading complex sugars into simple sugars which are necessary for the process. One such microorganism is the cellulolytic thermophilic anaerobe, Clostridium thermocellum. However, engineering improvements are needed before this organism will be economically viable in commercial fermentations. A complete metabolic model was developed for evaluating the carbon flux distribution through the metabolic pathway of Clostridium thermocellum in terms of milli-equivalent carbon per gram dry cells per hour. The model was derived from steady state stoichiometric equations of the biochemical network. A carbon recovery (%) analysis confirmed that the model including the central metabolism and biomass formation accounted for the majority of carbon. The importance of including the G1P/G6P network node into the model was verified, resulting in more reliable model performance.